Impregnated fibrous block



Jan. 2, 1934. G. .LwARD I IIPREGNATED FIBROUS BLOCK Filed Jan. 22. 1.930

IN V EN TOR. Z-wg i A TTORNEYS.

Patented Jan. 2, 1934 UNITED STATES PATENT OFFICE i 1,941,769IMPREGNATED Fnmons BLOCK Gilbert J. ward, l'srooklyln N. Y., assigno'rto Cheesman-Elliot Co. Inc., Brooklyn, N. Y., a corporation of New YorkApplication January 22, 1930. ySerial No. 422,52'3

3 Claims.

tured, and to the provision of a process by which v .such blocks may beproduced with uniform im' pregnation.

More specifically, the invention has for its object, the provision ofimproved boards of the character indicated which retain their initialsound and heat insulating properties and attain by treatment arelatively high degree of mechan ical strength and other properties,including weatherproof qualities.

Still another object is to provide an improved process by which thedegree of impregnation can be accurately controlled at all times andthus produce impregnated boards which have substantially uniformpenetration and unimpaired heat and sound insulating properties.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the several steps and the relationand order of one or more of such steps with respect to each of theothers, and the article possessing the features, properties, and therelation of elements, which are exemplied in the following detaileddisclosure, and the scope of the application of which will be indicatedin the claims.

For a fuller understanding of the nature and objects of the inventionreference should be had to the following detailed description taken inconnection with the accompanying drawing, in which:

Fig. 1 is a perspective view of an impregnated board constructed inaccordance with the invention, a corner being cut away to assist inillustration; and

Fig. 2 is a fragmentary sectional view showing the nature of theimpregnation. f

. It has been` proposed to prepare building boards, blocks, and' thelike from compressed mineral, animal and vegetable fibres, manufacturingthe same into structural and heat-insulatingv bodies which have as theirchief constituents .such materials as mineral wool, asbestos, celluloseflbres, Wool, hair, etc. It has also been attempted to coat such bodieswith pitch, tar, asphaltum, sodium-silicate and like materials,

Y by painting thesame thereon, or by dipping the bodies into suitablebaths of the coating material.

Such bodieshave relatively great capillarity and characteristics in adegree adapted for the comlarity is furtherrincreased where a waterproofit has been found that the coating is relatively porous and that thedegree of penetration is far from uniform, such coating materialfrequently running together at points Within the body, destroying itstexture and otherwise interfering with its .structural andheat-insulating properties.

By the present invention, boards of brous material are employed whichare highly compressed. Such boards may have a certain amount ofrelativelylarge pithy bres more or less uniformly 55 distributedthroughout the block' andl may if desired, be initially sized with awaterproofing composition, whereby the compressed fibrous body is highlyrepellant to moisture remaining relatively` dry, so that it does notreadily become' soggy. Such bodies in order to retain their sound andheat-insulating properties relatively unimpaired must be keptsubstantially dry and clean,-a condition which has not been maintainedin fibrous building boards heretofore, because of the iniiltration ofmoisture and dust laden air through the pores of the material.

Compressed fibrous boards which have these mercial practice of thepresent invention, are

made up largely of small densely compacted bres which may average in theneighborhood of about one-thousandth of an inchin diameter or crosswisedimension, While their lengths vary more widely, but are of the order ofone hundred times greater than their crosswise dimension. Such boardswhen relatively `highly compressed have no pore or cell openings of adefinite or regular size. Voids, however, exist between the interlacedfibres which are of asize of the order of 9 their vcrossvvise dimension.This property, together with the enveloped air imparts to the boards arelatively low capillarity, so that no great elevation of water can beeffected. This low capilsizing for the fibrous material is employed.Boards possessing these characteristics are now obtainableon the openmarket, certain of which contain relatively large amounts of coarselibres, moreor less uniformly distributed with the interlaced material,and are sold under the trade names, as lfor exampla. Celotex,

Such boards by reason of these properties vare adapted for u on'theinteriorsv of buildings as a `105 lstructural base -or iinish, but themechanical conditions, they readily become filled with mois-4 ture anddisintegrate.

In the practice of the present invention, boards which contain jhighlycompressed small fibrous 5 material having no definite pore structureare substantially uniformly impregnated to a predetermined depth withmaterials such as asphalt,

pitch, tar, resix, halowax and the like, in a manner whereby anon-porous homogeneous exterior 1o u surface results and there remains adefinite unimpregnated interior core portion permanently shielded fromVthe action of moisture or weather conditions.4 The infiltration of airof different temperatures and humidlties which may also be dust ladenwith the attendant loss of desired properties, is thus avoided. Theblock in consequence retainsits initial sound and'rheat-insulatingproperties substantially without change. The impregnated surface layernot only prevents disintegration but also imparts strength to thematerial of a character suiilcient ,to enable it to be used in eirteriorconstruction where it is subjected to relatively high stresses due tooverhead loads or wind. Y j The impregnation is carried out so as toleave no sln'face coating on the board or block, as will be apparentfrom thel reference to Figure 1 of the drawing, in which the large andsmall fibres at the surface have the same appearance as at the innerunimpregnated portion. It will be apparent, therefore, that the textureof the original surface remains substantially unchanged afterimpregnation.

There may be occasions where, for obvious reasons, it is not best ornecessary that both sides of a block be impregnated. In such cases thetreatment of the block may be limited to any desired portion of theReferring to the drawing, 10 denotes a building board. composed'ofcompressed small interlaced,

fibres with larger fibres dispersed therein, having no definite sizedcapillary passages; the Ylonger fibres of the board being indicated at11 on the exterior thereof and at l2 on thelinterior. The fsmall fibresare indicated'by the stippling 13.

The impregnating material here is indicated at 14 by the heavycross-hatching. There is shown a line of definite demarcation at 15indicating the interior boundary between the impregnated outer -shellandthe non-impregnated core which is composed of the unaltered initiallycompressed iibrous interlaced material.

The impregnating material, whether of asphalt, pitch, tar,resin,.halowax,l or the like, is of a u character which may be readily broughtto a desired iiuid condition adapted for -treating the,

'A board, but readily hardens 'and becomeslike a homogeneous solidafter`the treating conditions have been withdrawn and normal conditions areVf restored. A relatively hard asphalt is preferred as the impregnatingmaterial, since the treating condition is attained 'ny the applicationof a lmoderate heat. When melted, it is relatively uid, and when cooledimparts a relatively high ggf-degree of mechanical strength tothefibrous.

board. Uniform penetration for a material distance through all of theouter surface is readily' attained. Where a hard asphalt has thus beenmade to penetrate for a distance'from ene-fourth 'ze to one-third thetotal thickness of. a block approximately one-half inch in thickness,the increasein mechanical strength under all usual conditions of usewill be of the order of while at the same time the to weather t:conditions is increased in the order of 1.000% or tenfold. Theresistance to puncture which such impregnation imparts is of the orderof from 100% to 300%. The strength of the bond which suchlimpregnatedboard makes with nails, is inl creased by impregnation of this characterin the order of 300% to 400%. The resistance to tearing is alsoincreased by such impregnation in the order of 100%. j

In order to produce impregnated fibrous boards, blocks, and thelike,'which have an unimpairedcore, it is essential that the degree o fimpregnation shallrbe regulated and kept uniform, and since the boardpossesses relatively poor capillarity, the impregnating material isforced into the same by means of a suitable application of pressure orits equivalent, and the flow regulated by control of viscosity, so thatthe degree of impregnation may be determined. Since the impregnatingmaterials here employed are readily brought initially to a fluidtreating condition it is seen that the rate of ilow into the board orblock l is a function of the time of treatment; in general it is alinear function so that by properly timing the treating process,impregnation of the blocks may be had to any desiredrdepth and may bereproduced at will with uniformity. Pressuresand temperatures may alsobe varied to the same end.

A suitable process for impregnating boards of the present invention,involves first freeing the block of air from its interior structure andthen forcing the impregnating material in a fluid condition to flow intothe block for a predetermined time. When such periodA of time haselapsed, the flow is stopped and the impregnating boards withdrawn andpermitted to harden. The following is an example of the manner in whichthis process may be carried out: A

Y Atreating chamber is provided which may be hermetically sealed andlhas a vacuum pump connected thereto. This treating chamber is initiallyopened and is adapted to receive frames supporting the lboards to betreated.' These frames may be of any suitable construction, such assteel frames adapted to support superposed blocks in spaced relation.Frames containing the boards to be treated, for example, Celotex boards,are iirstplaced in the treating chamber which is then sealed and thevacuum pump applied. A vacuum of 27 inches is preferably obtained inthis manner; the vacuum being held fora treating period of approximately5 minutes. Suitable iiuid impregnating-materialis then flowed into thetreating chamber under full vacuum, for example, hot asphalt is thusflowed inat a temperature of 392 F. Such asphalt 130 is permitted toiiow into the treating chamber until substantially. atmospheric pressureagain obtains in the chamber; the asphalt being kept hot'during thetreating period by the employment of a suitable heating means inconiunction with the treating chamber, such as a jacket on the chambersupplied with saturated steam at 'l5 pounds gauge pressure, or withheated oil.

The treating period'here directly determines the degree of penetration.In the case of Celotex 140 boards, it is found that a treating periodof. 5 minutes attains a. penetration to the depth of Y substantially 56of an'inch on each face, so thatl there is left a clearly Ydefined corein blocks one- Y halfinch or'more thick, the insulating charac- 145teristics of which are in no way altered by the treatment.

when the treating period is over, the vacuum being broken, the asphaltremoved, and the Amiti-ds drained, the treating chamber may lbe opened,the frames withdrawn and the impregnated blocks then' permitted to cooland the asphalt to harden.

In the case of brous insulating boards to which the present inventionparticularly refers, it has been found that by the use of animpregnating compound having a viscosity of 11,300 seconds, Sayboltuniversal viscosimeter, at the operating temperature, and with otherconditions previously described remaining the4 same, an impregnation toav depth of 1;/8 inch is secured within the time limits of ve to tenminutes soaking in the compound under atmospheric pressure.

In the case of fibrous insulating boards to which the present inventionapplies, if the vis- Acosity of the impregnating compound be keptbetween the limits of 5,000 and 15,000 seconds (Saybolt universalviscosimeter) at the operating temperature, impregnation to a depth ofV8 inch is secured in five minutes, with other conditions previouslydescribed remaining the same.

'Ihe boards or blocks thus impregnated have the color when dry that isimparted by the impregnating material which is substantially .theirpermanent. color, as fibrous blocks of the present character are notreadily painted with ordinary paints nor does such paintadhere wellthereto.

Where it is desired to impart colors to the boards and blocks of thepresent invention, this may be accomplished by suitable pigmentation ofthe impregnating/material, since by this means, color is permanently anduniformly distributed over the surface, and penetrates the same t'o anydesired depth. Color fastness is thus obtained and liability todeterioration avoided. Any suitable pigment material may be employedwhichcan be admixed with asphalt, resins, waxes, etc., without liabilityof having their color affected thereby. 4

It is to be understood that by the term exterior faces as used in therst claim, is meant `ical values of the board and so as to leave subtheareas of the board or block which would be exposed during use, or whichare to serve as heatinsulating or sound-insulating surfaces, and doesnot include edges, or edge' portions which would not be exposed duringuse, or which ting, non-exposed surfaces.

Since certain changes in carrying out the above process, and certainmodifications in the article Patent dated January 2, i934.

assignee, Mastz'c'Asptalt Corporation.,

form abut-` which embody the invention may be made without departingfrom its scope, it is intended that all matter contained in the abovedescription, or shown in the accompanying drawing, shall be interpretedas illustrative and not in a limiting sense.

Having described'my invention, What I claim as new and-desire to secureby Letters Patent is:

1. A heat and sound insulating fibrous board or `block which comprises acompacted, looselyassociated fibrous material, such as Celotex or thelike, the exterior faces of said board or block being substantiallyuniformly impregnated from the surface thereof to a substantial depthwith a relatively hard asphalt or the like material in a manner -toleave substantially unchanged the texture of the original surface and toleave an unimpregnated inner portion shielded by said impregnated.portion.

2. A heat and sound insulating fibrous board or block which comprises acompacted, looselyassociated fibrous material, such as Celotex or thelike, the exterior portion of said board or block being substantiallyuniformly impregnated inwardly from the surface thereof to a substan- Atial depth with a material from the class including hard asphalt, pitch,tar, resins and halowax,

to materially increase the mechanical values of the board and so as toleave substantially unchanged the textureV of the original surface andto leave an unimpregnated inner core shielded by the said impregnatedportion, whereby the structure is improved as to its heat-insulating andsound-proofing qualities.

3. A heat and sound insulating fibrous board or block which comprises acompacted, looselyassociated fibrous material, such as"Celotex or thelike, the exterior portion of said board orblock beingsubstantiallyluniformly impregnated inwardly from the surface thereof toabout onefourth of its thickness with a material from the classincluding hard asphalt, pitch, tar, resins and halowax,tomateriallyincrease the mechan- .whereby the structure is renderedheat-,insulating and substantially sound-proof.

GILBERT J. WARD.

LAIMER'L Y l,94vl,769.-G11lbert J. Ward, Brooklyn, N. Y. IMPRGNATEDFIBRoUs BLoCK.

Disclaimer filed May 13, 1942, by the Hereby enters this disclaimer toclaiml of said Letters Patent.

v[Oljrmal Gazette June 16, 1.942.] y 1-

